LONDON (AFP) - Britain's Prince Charles joked on Monday that his son Prince William's baby was "hopefully" on the way, but wife Camilla went further, saying it could arrive "by the end of the week".

With William's wife Catherine due to give birth any day, Charles and Camilla started their annual summer tour of the south-west county of Cornwall and neighbouring Devon.

On their visit to the seaside town of Bude, the heir to the throne came face-to-face with some newborns.

Bude resident Trudi Lindsay brought along her three-week-old baby Ellie-Mae to see the royals.

"I said, 'You have got one of these coming soon' and Charles replied 'Hopefully', then he laughed," she said. "He was very good with Ellie-Mae, he touched her cheek."

But Camilla appeared to give away more at a speech to assembled guests.

"We are all just waiting by the telephone," she said. "We are hopeful that by the end of the week he or she will be here."

A spokesman from Clarence House later confirmed the comment.

Charles and Camilla drew loud cheers from the flag-waving crowds as they walked through the town.

Ms Jenny Dawe, 62, who works in a local shop, showed the royals her selection of cards.

"I said, 'You will need a new baby card soon' and they laughed," she recounted.

New parents Poppy and Paul Steen brought their five-day-old son Lowen to meet the royal couple.

"The midwife did joke that he might arrive on the same day as Kate's and we might get a commemorative coin but Lowen wasn't waiting for that," said Mr Paul Steen.

All babies born on the same day as William and Kate's imminent arrival can register to receive a free lucky silver penny from the Royal Mint, worth 28 pounds (S$53).